PROJECT SUMMARY The overall goal of this 5-year Mentored Research Scientist Development K01-Award is to support Henna Budhwani, PhD, MPH become an independent investigator in the field of HIV prevention. The proposed project seeks to address the HIV crisis in Alabama, where rates of undiagnosed HIV in black young men who have sex with men (YMSM, 18-29 years) exceed 20%. This project will adapt and test a behavioral intervention to promote HIV rapid testing in the community, deliver culturally appropriate prevention education, offer sociostructural supports, and refer eligible participants for pre-exposure prophylaxis (PrEP). Four training objectives are proposed that are in lockstep with three specific aims. Objective 1 includes an intensive training and mentoring plan in social theory including theories of intersectionality and emerging masculinities. Objective 2 includes in- depth training on qualitative research methods including how to conduct focus groups, in-depth interviews, and qualitative data analysis. Aim 1, which will be conducted after Objective 2, is to elucidate experiences, beliefs, and predictors related to delivery and utilization of HIV testing and prevention services by black YMSM using qualitative research methods, namely in-depth interviews with HIV outreach staff, focus groups with black YMSM, and in-depth interviews with members of key sub-groups (e.g. transgender women) to inform the adaptation of the Brothers Saving Brothers (BSB) intervention. Objective 3 includes didactic and hands-on training on how to scientifically adapt HIV behavioral interventions using validated frameworks, such as intervention mapping. Aim 2 is to adapt the BSB intervention to include two HIV prevention tools (rapid testing and PrEP), to address structural barriers, and to be acceptable to black YMSM in Alabama. Objective 4 includes comprehensive training and mentoring in the field of implementation science. Aim 3, which concludes the proposed research study and K01 project, is to conduct a hybrid type 1 effectiveness-implementation pilot study of the adapted intervention in which the candidate will a) assess acceptability and feasibility of adapted BSB (aBSB); b) preliminarily estimate effects on HIV prevention outcomes; and c) collect data on real-world implementation. These aims will be accomplished by collaborating with two community-based organizations that are well-respected for their HIV prevention work in study communities. This rigorous project includes intensive training at the candidate's home university, the University of Alabama at Birmingham (UAB) and from other prominent institutions that offer very specific training not found at UAB; engagement within the Adolescent Medicine Trials Network for HIV/AIDS Interventions (ATN); comprehensive mentoring from senior HIV researchers with expertise in minority, youth, and MSM health; and a thoughtful research strategy that addresses significant threats, high rates of undiagnosed HIV and insufficient engagement with HIV prevention services, including PrEP, in black YMSM in Alabama. The combination of the proposed mentoring and training with study findings will culminate in the candidate's attainment of independence and development of a full-scale, implementation science R01 proposal to test aBSB.